Swing
a cat

: No room to
swing a cat may come from Mark Twain. I remember him describing a room as being
too small to swing a cat in. Possibly in Innocents Abroad.

Here's what I found
out about the origin:
If there's not enough room to swing a cat then space
is very tight; the room is very tiny. The cat in this instance is said not to
be of the Pussy variety but, rather, o'nine tails type. The nine thronged whip
was used as punishment at sea. Because space was at a premium below decks there
was not enough room to wield the whip; in consequence the whipping always took
place on deck.
Evidence against the above origin comes from the fact that
the expression was in use in the 1500s and the cat o'nine tails was not invented
until the mid 1600s. Thus it may be that the saying truly involves felines, since
there used to be a "sport" of swinging cats by their tails as targets for archers.